Bovine Fibroblasts Response to Foot-and-Mouth Disease Virus: Influence of Integrins and Soluble Factors in Resistance

Abstract

Foot and mouth disease may be the most economically devastating animal disease nowadays. Blanco Orejinegro (BON) cattle are one of the native creole breeds from Colombia; this breed carries important genetic traits for survival and reproduction in the tropics showing in vitro and in vivo resistance to pathogens. Here we evaluate primary fibroblast cultures of BON cattle for their phenotypic resistence/susceptibility (R/S) polymorphism toward FMDV, and to determine whether a correlation exists between the R/S polymorphism and expression of integrin αV-β3, and/ or the antiviral activity in the supernatants of those cultures. Our data show that different R/S patterns to FMDV in vitro. Between 2% and 85% of the fibroblasts in the PCF-BON samples expressed integrin aV-b3. Interestingly, a correlation between R/S and expression of this receptor was observed for the A24 FMDV subtype. Highly resistant cultures showed a low level of integrin expression. Furthermore a correlation was observed between resistance and antiviral activity (AVA) of supernatants from infected samples. Supernatants with high AVA were always from very resistant samples for subtype A24, or from very resistant or resistant samples for subtype O1; supernatants with low AVA were from susceptible samples. In most samples, the factor in the supernatants responsible for AVA was not only resistant to heating, but AVA increases after heating. To our knowledge, this is the first report showing resistance to FMDV infection in vitro using primary cultures from bovines.